Work on Lymphatic Filariasis (LF)

The Lymphatic Filariasis (LF) elimination programme in Ghana has achieved tremendous success through the mass drug administration (MDA) campaign and many regions have met the criteria to scale down distribution. Although MDA for LF has been conducted in an increasing number of communities for over 15 years in Ghana, the infection prevalence is highly varied and hotspots (areas with ongoing parasite transmission) persist in some parts of the country. It is likely that these variations are driven by differences in access to drugs, drug uptake, and local mosquito diversity, abundance, and biting rates. It is pivotal therefore, to assess both the success and the prospective timing of elimination in different settings at regional, community and individual level (including by gender).  

The aim of the research in Ghana was to provide evidence to support rapid and sustainable scale-up of complementary intervention strategies to eliminate lymphatic filariasis in Ghana. This was achieved through evaluating the social, entomological and epidemiological characteristics of hotspot communities to identify the causes of persistent transmission, alongside evaluating the impacts of an integrated MDA and vector control programme on service delivery, community participation and LF transmission.

The collected information was used to identify opportunities for better planning and co-implementation of the interventions at the district and community level. Tools were developed to inform scale-down of interventions, including the application of disease transmission models to predict the impacts of interventions on lymphatic filariasis to help setting locally relevant targets for elimination, and the evaluation and optimisation of available and emerging tools for the sensitive detection of the parasite in the mosquito vectors for post-MDA surveillance.

COUNTDOWN has been generating evidence on the social acceptance and cost-effectiveness of alternative strategies for implementation in "hotspot" areas or in post-MDA endgame scenarios, where test and treat strategies become more cost effective and deliverable. COUNTDOWN has worked to identify "hotspots" and predict the impact of MDA and vector control on LF transmission. In addition, the feasibility and cost of integrating long-lasting insecticidal ned (LLIN) distribution with MDA was assessed and evaluated on how vector characteristics might influence the impacts of LLIN. 

Work on Schistosomiasis

Mass Drug Administration (MDA) of Schistosomiasis (SCH) and Soil-transmitted Helminthiasis (STH) requires rapid scale-up to achieve the 2020 target. COUNTDOWN has been evaluating how to deliver equitable drug delivery to currently excluded populations, in Cameroon and Ghana. 

EXPANDED ACCESS TO SCHISTOSOMIASIS CONTROL 

The main aim of the project was to develop innovative strategies for expanded access of treatment and improved diagnostic tools for schistosomiasis (SCH) and Soil-Transmitted Helminths (STH) in Cameroon and Ghana.

The specific objectives were:

1. To conduct targeted baseline parasitological and epidemiological surveys to describe infection levels of schistosomiasis and STH, and associated morbidity indicators

2. To assess expanded annual community treatment in reducing prevalence of schistosomiasis and STH

3. To assess community understanding of the current MDA programme and its strengths and weaknesses and economic aspects of whole community treatment.

4. To assess the acceptability and feasibility of introducing an alternative treatment strategy to the current treatment regimen from different perspectives

5. To investigate different levels of access and factors influencing scale-up to PZQ and ALB treatment in areas with limited treatment coverage

The studies were conducted in communities’ endemic for SCH/STH in Ghana in low and high-transmission settings. Social science research outputs and impact on parasitological and general health indicators were monitored at baseline and follow-up timepoints.  The data generated by the community screening were fed back into the Ministry of Health and helped inform mass drug administration, continuous community surveys will then monitor the success of the intervention. More on this in this research paper.

DIAGNOSTICS

A novel opportunity to scale-up diagnostics was investigated by co-opting samples from the Global Polio Laboratory Network and screening these for STH and schistosomiasis. The Global Polio Laboratory Network (GPLN) comprises 145 laboratories spread throughout the world. Across Africa, there are 16 GPLN laboratories which received around 22,017 samples per year to screen for polio. The polio control programme has been hugely successful and will leave a legacy of expertise in surveillance and disease control. COUNTDOWN partnered with the GPLN to explore cross-disease partnerships and utility of their infrastructure and expertise to survey for NTDs.

The aim of this study was to assess the suitability of samples collected at a GPLN laboratory for their use in the screening of soil transmitted helminths and parasites that cause schistosomiasis. The Ghanaian GPLN laboratory, based at the Noguchi Memorial Institute for Medical Research, Accra, was selected to carry out the assessment. To assess the suitability of the GPLN for screening neglected tropical diseases, COUNTDOWN screened the faecal collection for six pathogens.

COUNTDOWN carried out DNA extraction on the faecal samples and performed a highly sensitive DNA analysis assessment. Using this method, it was possible to screen for multiple worms within the same reaction using a highly sensitive and specific test. If proven that the faecal collections of the global polio laboratory network are suitable candidates for the detection of parasitic worms, this technique can be used to develop a cost-effective and sustainable means of monitoring intestinal worm and schistosomiasis prevalence in resource poor countries.

For further reading please see this research paper.